The first cast I made of my own foot in fly ash revealed not only my own dermals, but other spontainously produced ridges as well.

So now I wanted to get a control cast. I built an impressioning tool by gluing a section of smooth virgin plastic to a 2 x 4. I placed the smooth plastic surface onto the fly ash bed and stepped on it. I cast the resulting rectangular impression with Hydrocal B-11 This is the result:

Note how the ridges cluster next to the furrows:

Note that these ridges are fairly small, not much bigger than human dermal ridges. As we will see later, the ridges on CA-19 that are claimed to be “dermal ridges” are much bigger. Eventually I would come to call these spontaneous ridges “desiccation ridges”, due to the input of Dr. Anton Wroblewski, a geologist.

I eventually obtained a copy of CA-19 for myself to study:

The ridge textures seen in the next two photographs are from copies that Jeff Meldrum had on display the Bellingham Sasquatch conference in 2005. As you can see, the ridges are quite detailed and obvious. These two photographs show the ridges on the medial (inside) aspect of a right foot:

The next photo is of a band of ridges that arcs laterally across the heel of the cast, whose margin is about 9cm anterior of the posterior edge (heel) of the cast. This is the actual CA-19 cast, which Meldrum claims is the original cast:

I continued to pour cements over various dry powdery substrates to see what would happen. I could find no information on the subject on the Internet, and I didn’t know where to even start looking in a library, so I was really “going it alone”. For cements, I tried Hydrocal B-11, Ultracal 30, and plaster of Paris.

As I continued to test various cement and substrate combinations, I learned subtle details of what happens when cement slurries interact with dry, powdery substrates. I noticed that a great deal of water flowed from the slurry into the dry powder during the time the slurry was setting up. This made sense, as fine dry powders often exhibit strong capillary action or a “wicking” effect. My first clue that the wicking of water from the cement slurry to the substrate was involved in the desiccation ridge process came from a post on an Internet forum by a Bigfooter promoting himself as a “casting expert”.

“The only reason to use hair spray or aerosol lacquer is to set into place those fine details such as is found in dust that can blow away. I would not use talc in snow. The proper method is to put Potassium sulfate in the plaster mixing water to lower it’s freezing point and then to use spray wax on the track to seal it from pouring the plaster mix through.

You do not want any wicking action to take place. This can produce misleading surface detail artifacts.” (Italics mine)

This gave me a feeling that the “casting expert” was familiar with the process I was investigating though he claimed he was not.

Over time, I had a number of encounters with the casting expert. I began to form the opinion that this individual was not a forthright and honest person. Eventually I came to the conclusion that his interest in “documenting” my tests was essentially a way of obtaining free content for use on TV shows or DVD’s.

Eventually it came to light that the “casting expert” was trying to pass off a cast of an elk lay as strong evidence of Bigfoot. My final encounter with this individual was an on-camera interview for a TV show he was producing. What he said he was going to ask me and what ended up actually being asked were two entirely different things.

The “casting expert” provided little or no positive input into my investigations, and so I feel no need to provide any mention of him.

Lets take a look at some test casts to see what desiccation ridges look like.

Note that by this point in my investigations I was getting more serious about documenting exactly what I was doing. Note that I’m testing Ultracal 30 and not plaster of Paris, which Green used to make his cast. Why? Well, I’m simply trying to illustrate that this is a generalized process, sort of like how paint can sometimes “orange peel”. The orange peeling of paint is a generalized process, not dependant on one brand of paint or substrate. Similarly, the desiccation ridge process is also a generalized process. As we will see, the real “money shot” test casts that I will compare to Green’s cast all use plaster of Paris. I’m choosing to include this particular cast, as it illustrates that desiccation ridges can occur in natural soil, not just semi-synthetic fly ash.

Note how the ridges tend to cluster in bands around the periphery of the cast.

Another important feature I discovered is that when cement slurries are poured onto powdered substrates, they often leave a subtle ring in the resulting cast at the point of first contact. From there, desiccation ridges often form in concentric bands with the point of first contact as a center. The following photograph illustrates this ring feature:

An analogy to what we see here in cement is commonly seen in trees. You don’t have to be a dendrologist to recognize where a log section started out as a sapling. The red ring I’ve included here is ridiculously redundant:

Another analogy is the way waves propagate away from a stone thrown into a pool of still water. In both cases, the point of origin can be inferred from the rings or waves at the perimeter. While it may sound like a trivial detail, it is really rather important; if a cement slurry is poured into a track as a stream (and not “splash cast”) the slurry must land at some particular spot. If the slurry continues to fall on that spot, the advancing slurry will flow away from that spot with a curved leading edge, just like the curved waves from a rock thrown in water.

And let’s review again what we saw in my first rectangular test cast; furrows. Furrows in these casts are a result of a momentary stall of the slurry flow laterally across the surface of the substrate. How do I know this? Simple; watch carefully as you pour the slurry. When you see the leading edge of the slurry momentarily stall, make a mental note of where this happened. You will see an arc in the resulting cast.

The following test cast was a bit of a lark; I call it “trigfoot”, but it illustrates nicely the features we need to see.

First off, you should by now be able to see where the cement slurry first contacted the substrate. You can see it clearly in this close up:

Can you see the subtle bands of ridges that form in concentric circles, whose center is the point of first impact? Do you see the large furrow? The furrow is so pronounced here it is almost a “shelf”, yet is simply where the cement slurry stalled when spreading across the substrate. Here is a close-up:

Note how ridges abut the furrow. Also, you can see desiccation ridges on the side of the cast, which is part of the slurry overflow. This will factor into our equation later.

The next two photos are of plaster of Paris test casts. Unfortunately I made them before I realized how much of a “splash” all this would make, and I failed to record pertinent information. I believe both casts were made in soil I obtained from the Duwamish river bank. Both casts demonstrate very clearly how a major furrow can spontainously form at a distance away from the point of first impact.

Note how the desiccation ridges cluster next to the major furrows.

Now lets take a step back and see what the CA-19 cast looks like in a different way. The following image was created by Jeff Meldrum and appears on page 258 of Sasquatch: Legend Meets Science. To create the image, Meldrum applied a release agent to the cast, then painted latex over it. Once the latex dried, it was peeled off and coated with lotion. Fingerprinting powder was applied to that, and then adhesive tape over that. The adhesive tape lifted off the powder lightly adhering to the ridge peaks. The tape was placed on paper, and scanned. I’m impressed by Meldrum’s technique and attention to detail. This is the result:

Remember, we are looking at a right foot, so you will have to imagine this as a dorsal view, not a plantar view. The medial side of the cast is at the bottom in the above photo. Now lets highlight a particular feature:

Do you see the ring inside the red circle? During the late 1960’s, everyone simply poured cement slurry into the track; no one used “splash casting” at that time. This is how Green made his cast on Onion Mountain. His slurry had to land somewhere, producing a point of first impact. You can see such a circle in the center of this image, so it is a reasonable inference that this is indeed the point of first impact.

The next image has a thin ellipse added to highlight where the major band of ridges is located on this cast.

The medial side of the cast gets all the attention, but if you look closely, you can trace the band of ridges all around the periphery of the ellipse I have superimposed. Note too, how some of the ridges seem to taper off in the same manner that you saw earlier in my own foot cast, a thick ridge will bifurcate off in a sort of “dendritic” manner.

Now we begin to get into why this cast looks more like it is exhibiting desiccation ridges and not dermal ridges. The ridges we see here are behaving like known desiccation ridges in that they are clustering in a roughly concentric ring around what is probably the point of first slurry impact. Many of the test casts also exhibit another feature seen here; a bare space separates the point of first slurry impact from the ridge bands. The band of ridges 9cm from the posterior margin of the cast is clustered next to a prominent furrow, a very common characteristic of know desiccation ridges. This band is on the right hand side of the above image. In this image the furrow adjacent to the band of ridges is darker and more pronounced.

Now if we imagine these ridges to be real dermal ridges, we must ask what kind of animal has an elliptic band of dermals on its foot? What kind of animal has a big bare patch of skin in the center of the foot with no dermals?

Something else that the Bigfooters never bring up, which is admittedly more speculative on my part is this; where are the flexion creases? How do putative Sasquatch casts come to contain detail as fine as dermal ridges, yet do not contain the much coarser features of flexion creases? If Bigfoot has a mid-tarsal break as Jeff Meldrum proposes, shouldn’t there be one or more large, deep, flexion creases? Take a look at real ape hands and feet sometime. I’m lucky to live in Seattle, which has a zoo with both gorillas and orangutans. Their hand and foot pads are very thick and have much deeper flexion creases than humans do. Why don’t we see these in purported Sasquatch tracks and resulting casts?

Let’s return to some test casts made with plaster of Paris and see how they match the CA-19 cast. Here is a test cast I made on May 19, 2005 using plaster of Paris over volcanic ash. Note the center circle which represents the point of first impact. Note the furrows which arc toward that center. Note the bands of ridges which also arc toward the center. Not all desiccation ridges occur at the periphery of the cast. Note how the band of ridges next to the ruler is separated from the point of first impact by several centimeters.

Compare the texture of the known desiccation ridges on top with the texture claimed by Jimmy Chilcutt to be “dermal ridges” in the CA-19 cast copy below. There is an obvious match in size and texture:

Another test cast comparison; plaster of Paris test cast made on 10-19-2006 on top, copy of CA-19 cast below. The 10-19-2006 test cast is discussed further in the Ridge Flow Pattern section: